Brake-shoe.



A. BRAKE.

BRAKE SHOE.

PLICATION -F|LED nsc .28, 1914.- 1,143,494. '-P&136I1136d June 15, 1915.

ARCHIBALD BRAKE, OF TORONTO, ONTARIO, CANADA.

' BRAKE-SHOE.

iaaaaea.

Specification of Letters Patent. Patented June 15, 1915.

Application filed December 28, 1914. Serial No. 879,382.

To all whom it may concern Be it known that I, ARCHIBALD BRAKE, asubject of the King of Great Britain, residing at the city of Toronto,in the county of York, Province of Ontario, Canada, have inventedcertain new and useful Improvements in BrakeShoes, of which thefollowing is a specification.

This invention relates to a brake shoe of the type in which the body ofthe shoe is cast on a back of tough steel or malleable iron, and myobject is to devise a brake shoe of this type which will be strong,easily made, and in which the lug forms a satisfactory bearing for thekey which is used to secure the shoe to the brake head.

I attain my object by forming the back of an integral steel plate whichis folded at the center to form a lug of twice the thickness of theplate through which the hole for the key is formed. The top of the lugis upset and flattened to increase the bearing surface for the key andthe extent of the engagement of the lug with the cast metal.

The invention is hereinafter more fully described and is illustrated inthe accompanying drawings in which Figure 1 is a longitudinal section ofa brake shoe provided with my improved back; Fig. 2 a perspective viewof the back itself; Fig. 3 a cross section of the brake shoe; and Figs.4c, 5 and 6 details in side elevation of parts of the back showingdifferent stages in the evolution of the upset top of the lug.

In the drawings like numerals of reference indicate corresponding partsin the different figures.

1 is the back formed of a tough steel or malleable iron. This is formedof a strip of metal having beveled edges 2, and preferably having aseries of holes 3 formed therein. Centrally the back is first doubled,and then each part is bent outwardly at right angles a short distancebelow the bent, so that a lug 4 is formed at the center of the backcomprised of two thicknesses of the strip. The strip adjacent the lug isbent downwardly somewhat as shown, and curved into the metal of the lug,so that the surface of the strip adjacent the lug is somewhat below thecurved surface in which the upper part of the back lies.

The top of the lug is upset so as to expand it longitudinally of thebrake shoe to increase the thickness of the lug at the top, andimmediately below the expanded portion the hole 5 for the key used tosecure the brake shoe to the brake head is formed.

The increased thickness of the lug due to the upsetting of the upper endgives the lug a greater bearing surface on the key, which prevents unduewear. The greater amount of metal thus secured above the key givesincreased strength at this point where the strain is greatest.

Preferably the upsetting is complete as shown in Fig. 6, though the endmay be partially upset as shown in Figs. 4 and 5 and a considerabledegree of utility obtained.

On the back is cast the body of the shoe, the cast material overflowingthe beveled edge of the back and extending up through the holes 3. Lugs6 are cast at each side of the shoe, which embrace the ends of the lug41- as shown particularly in Fig. 1. The upset upper end of the lug 4gives the lugs 6 a better engagement with the cast metal than if the lug4: were of the same thickness throughout its height.

The brake shoe formed with the back substantially as above described andshown in the drawings will be found to be strong and durable, and alsoeasily made.

What I claim as my invention is 1. A back plate for brake shoescomprising a metal strip doubled at the center and bent to form anupstanding lug of two thicknesses of the strip, the top of the lug atthe bend being upset to give the lug a greater thickness at that point,and a hole for a key being formed through the lug below the upset topportion.

2. A back plate for brake shoes comprising a metal strip doubled at thecenter and bent to form an upstanding lug of two thicknesses of thestrip, the top of the lug at the bend being upset to give the lug 1,Signed at Toronto Can. this 21st day of greater thickness at that point,and a hole Deoember 1914: in the presence of the tWo for a key beingformed through the lug undersigned Witnesses.

below the upset top portion, in combination ARCHIBALD BRAKE. 5 with a,shoe body cast on the back and Witnesses:

formed with a lug at each side embracing J. EDW. MAYBEE,

the ends of the lug of the back. i E. P. HALL.

Copies of this patent may be obtained for fine cents each, by addressingthe Commissioner of Patents, Washington, D. 0.

